Fungi/Transcript
Transcript A plate of mushrooms and a half-filled wine glass are on a table. Next to the wine glass is a wine bottle labeled "Purèe de Prune." Text reads: The Mysteries of Life with Tim and Moby. Moby is sitting at the table. Tim brings a covered tray to the table. He has a handle-bar moustache and a white towel is draped over his left arm. He speaks in a French accent. TIM: Monsieur, dinner is served. Tim puts the plate down on the table and removes the cover. It contains steaming mushrooms. TIM: Grilled Portobello mushrooms smothered in melted bleu cheese and a light duck jus! Moby has a big grin on his robot face. He holds a knife and fork in his hands. MOBY: Beep! Beep! Moby begins eating. Tim looks inside the plate and takes out a sheet of paper. Tim reads from the typed letter in a French accent. TIM: Dear Tim and Moby... Tim clears his throat and then starts over without any accent. TIM: Dear Tim and Moby, Why are funguses so gross? Sincerely, Princess. Not every fungus is gross. Ask Moby; he's eating some right now! Moby abruptly stops eating the mushrooms and looks concerned. TIM: Fungi are a diverse group of organisms that includes molds, microscopic yeasts, and mushrooms. They can be found in just about every environment on Earth, from forests to deserts and even beneath the ocean. Images show the types of fungi and environments that Tim describes. TIM: Scientists believe there are more than a million species of fungi and, so far, we’ve only identified a fraction of them! MOBY: Beep? TIM: Well, they're kind of hard to categorize. Like plants, fungi grow in one place and can't move around on their own. But like animals, they're heterotrophs, which means they get nutrients by consuming other organisms. Images show a mound of orange fungi, a few green plants, and three cows eating grass. Text reads: heterotrophs TIM: And like both plants and animals, fungi are eukaryotic, meaning each of their cells has a nucleus. An image shows a eukaryotic cell. It has an outer membrane that surrounds its various organelles and its nucleus, which is located at its center. Text reads: eukaryotic. TIM: Since they don't fit neatly into either the Plant or Animal kingdom, scientists created a separate category just for them: the Fungi kingdom! A close-up shows the mound of orange fungi. Text reads: Fungi kingdom TIM: There’s a lot of diversity within that kingdom, from their physical features to the ways they reproduce. MOBY: Beep? TIM: Yeah, most fungi share a few common traits. Zoom in on that mushroom! Tim points to one of the mushrooms on Moby’s plate. Moby's eyes extend toward the mushroom. TIM: The cells of fungi are arranged into long, thread-like structures called hyphae. An enlarged view of the mushroom fills the screen. The thread-like hyphae can be seen crisscrossing the mushroom. Text reads: hyphae. TIM: The cell walls are mostly made of chitin, a tough material that's also found in insect exoskeletons. A close-up shows individual cells surrounded by cell walls. Another close-up shows a beetle. Text reads: chitin. TIM: Hyphae grow at the tips, forming an interconnected network called a mycelium, which makes up the main body of many fungi. The image of the hyphae zooms out, revealing a vast network of threads. It zooms out further, showing a mushroom growing up out of the ground with a large network of tendrils extending from the bottom of the mushroom into the ground. Text reads: mycelium. MOBY: Beep? TIM: No, unlike plants, fungi can't produce energy through photosynthesis. Tim takes a moldy orange out of the refrigerator. TIM: Instead, they grow directly on food sources like soil, wood, bread; even dead flesh! Once inside the food, hyphae secrete enzymes, chemicals that break down organic matter into nutrients they can absorb. The hyphae's thread-like shape gives them a large surface area to absorb as many nutrients as possible! An image shows a mushroom growing out of the soil with hyphae extending into the ground. An animation shows nutrients moving up from the soil through these hyphae and into the main body of the mushroom. MOBY: Beep? Moby holds up a mushroom from his plate, showing it to Tim. TIM: Well, the bulk of a fungus usually grows out of sight, underground or inside whatever it's growing on. In mushrooms, the only part we do see is the fruiting body. A close-up zooms in to the upper portion of the mushroom. Text reads: fruiting body. TIM: It's made of special hyphae that don’t grow like the rest of the mycelium. Its only job is to produce spores, special cells used for reproduction. The view zooms in further to show the special hyphae. Some hyphae near the top disperse spores. Text reads: spores. TIM: In some fungi, the spores reproduce sexually; they have to join with another fungus’s spores to produce offspring. A diagram of two spores is shown. Each spore has 16 individual chromosomes. The two spores move together and merge into one. There are now 16 pairs of chromosomes. Text reads: sexually. TIM: In others, they're asexual; they can reproduce on their own. A single spore with 16 pairs of chromosomes splits into two spores, each with 16 pairs of chromosomes. Text reads: asexual. TIM: Many species can produce both kinds of spores! And yeasts usually don't produce spores at all. Instead, they reproduce through an asexual process called budding, where a new organism grows from a parent's body and eventually splits off. A fungi is shown with several spherical bumps protruding. The bumps grow larger and one of the bumps snaps off and floats away. Text reads: budding. Moby is now eating a sandwich. TIM: By the way, bakers rely on yeast to make bread! Tim points at the bread in Moby's sandwich. MOBY: Beep. TIM: You can't get away from fungi so easily, my friend. They affect our everyday lives in so many ways, bad and good. We've all heard about how some mushrooms produce deadly poisons! A view of a red mushroom is shown. A symbol of a skull and crossbones appears in front of the mushroom. TIM: And how some fungi can cause skin infections like ringworm and athlete's foot. A split screen shows the skin infections ringworm and athlete's foot. TIM: On top of that, fungi cause 80 percent of plant diseases! A view of some plants appears. Several of the leaves contain blotches. TIM: Still, life as we know it depends on fungi. They act as decomposers, breaking down dead stuff and recycling nutrients through the food chain! An image of a dead plant next to a dead animal is shown with mushrooms growing all around. Text reads: decomposers. TIM: Then there are fungi that have symbiotic relationships, or partnerships, with other organisms. Many plants can’t survive without special fungi that grow on their roots and help them absorb nutrients from the soil. A plant is shown. The image pans down to show its roots under the ground. An animation shows water and nutrients from the soil entering the roots and traveling up the plant. TIM: And lichens, which are combo of fungi and green algae, break down rocks into soil where plants can grow. An image of a number of rocks is shown. There are discolorations on the rocks. Text reads: lichens. TIM: We humans benefit from fungi even more directly. Most antibiotics, medicines that fight bacterial infections, are derived from fungi! Tim is lying in bed with a thermometer in his mouth. He is holding a box of amoxicillin. Text reads: antibiotics. TIM: And last but not least, we rely on fungi for food. Tim and Moby are at the kitchen table. Moby pulls back his plate and starts devouring the selection of eating mushrooms, cheeses, truffles, breads, and soy sauce on the table. MOBY: Beep! TIM: Hmm, bon appétit? Moby picks up a bottle labeled "SOY" and pours its contents into his mouth. Category:BrainPOP Transcripts Category:BrainPOP Science Transcripts